\documentclass{ctexart}
\usepackage{avanti}
\everymath{\color{Solarized-magenta}}
\pagestyle{empty} % 没有页眉和页脚

\tikzset{font=\normalsize}

 % define the plot style and the axis style
\tikzset{base/.style={smooth,thick,draw=Solarized-base01}}
\tikzset{arrow/.style={->,>=stealth,base}}
\tikzset{curve/.style={base,Solarized-blue}}
\tikzset{nc/.style={circle, base}}

\begin{document}

\begin{tikzpicture}

    \foreach \i in {-2,0,2}
        {
            \foreach \j in {2,4,6}
                {
                    \pgfmathtruncatemacro{\ip}{\i+1};
                    \pgfmathtruncatemacro{\jm}{\j-1};
                    \draw [base,fill=Solarized-base2] (\i,\j) -- (\ip,\j) -- (\ip,\jm) -- (\i,\jm) -- (\i,\j);
                }
        }

    \draw [base,fill=Solarized-base2] (10,3) -- (11,3) -- (11,4) -- (10,4) -- (10,3);

    \foreach \i in {-1,...,6}
        {
            \pgfmathtruncatemacro{\im}{\i-1};
            \draw [base] (\im,-1) -- (\im,6);
            \draw [base] (-2,\i) -- (5,\i);
        }


    \node at (5.5,2.5) {$\otimes$};

    \foreach \i in {6,...,9}
        {
            \draw [base] (\i,1) -- (\i,4);
            \draw [base] (6,\i-5) -- (9,\i-5);
        }

    \node at (9.5,2.5) {$=$};

    \foreach \i in {10,...,13}
        {
            \draw [base] (\i,1) -- (\i,4);
            \draw [base] (10,\i-9) -- (13,\i-9);
        }

\end{tikzpicture}

\end{document}

